North Carolina Department of Justice spokeswoman Noelle Talley confirmed the criminal investigation into possible public corruption, which she said began in 2013. Talley said the probe was prompted by requests from federal and state prosecutors in Raleigh.

Talley would not specify the targets of the investigation.

The Associated Press reported last year that political donations from an Oklahoma gaming software provider may have violated state laws prohibiting corporate money from funding political campaigns. The Republican campaigns of Gov. Pat McCrory, House Speaker Thom Tillis and Senate leader Phil Berger gave to charity thousands in donations from the tainted donor.

McCrory, Berger and Tillis have denied any wrongdoing in taking the donations from the software provider.

An Iranian military observation aircraft flew within 50 yards of an armed U.S. Navy helicopter over the Persian Gulf this month, sparking concern that top Iranian commanders might not be in full control of local forces, CNN has learned.